Push-button



S. ANTHONY.

PUSH BUTTON. APPLICATION FILED 106.21, 1915- RENEWED NOV- l3. 191:8.

1,340,139 Patented May 18,1920.

5/ 40 %Q 40/ //5 a? i 7 l/ I lzzvenlax l provide an improved push-button having a STANLEY ANTHONY, OF BOSTON, MASSACHUSETTS.

PUSH-BUTTON.

Specification of Letters Patent.

Patented May 18, 1920.

Application filed August 21, 1915, Serial No. 46,646. Renewed November 13, 1918. Serial No. 262,400.

To (ZZZ whom it may concern:

Be it known that I, STANLEY ANTHONY, a citizen of the United States, residing at Boston, county of Suffolk, and State of Massachusetts, have invented a new and useful Improvement in Push-Buttons, of which the following is a specification.

The present invention relates to push-buttons for closing signal circuits.

The object of the present invention is to cheap, simple, and compact construction in which the working parts are arranged for ready inspection for purposes of sale or re pair without requiring the disassembling of the push-button.

To the accomplishment of this object the features of the present invention relate to certain devices, combinations and arrangements of parts fully set forth hereinafter, the advantages of which will be readily understood by those skilled in the art.

The various features of the present invention will be readily understood from an inspection of the accompanying drawings, in which,

Figure 1 is an elevation of the push-button;

Fig. 2 is a longitudinal sectional elevation;

Fig. 3 is a perspective of the disk employed to separate the free ends of the contact springs;

Fig. 4 is a reversed perspective of the push-button plunger; I

Fig. 5 is an elevation, partly in section, of the terminal screw;

Fig. 6 is a plan of the bottom of the pushbutton;

Fig. '7 is a perspective of one of the contact springs, and

Fig. 8 is a detail showing the construction of the joint between the casing of the pushbutton and the cap therefor.

The complete push-button comprises a casing in which the contact elements are received and a plunger operable through the casing for closing the contact elements. t .he casing is made up of a cylindrical tubular body portion 1 having a head or cap 3 secured to one end thereof, which head or cap is provided with an opening to receive the plunger element by which the contacts are closed. I

The contact members of the push-button comprise a pair of springs 7 carried by the casing and a conical contact pin 8 carried by a plunger 9 which is slidably mounted in the body 1 of the casing. The plunger 9 is shown as formed with a transversely-extending slot 30 in which the pin 8 is received, said pin being in the nature of a projection extending from a block 31 that fits in said slot 30. The plunger is provided with a finger piece 10 which extends through the cap 3, and it is yieldingly held in its outward position by means of a frusto-conical spring 11 which is interposed between said plunger and an insulating disk 12 on the bottom 5. The contact springs 7 extend through the bottom 5 and their upper ends terminate within the slot 30. Each spring is clamped to the bottom 5 by a metallic bushing 13 which is swaged into the bottom 5, (Fig. 2). The springs 7 are normally under tension tending to cause the engagement of the free ends thereof.

In order to hold the free ends of the springs apart and thus maintain the circuit open the bottom of the plunger 9 carries a separator 14 (Figs. 2 and 3). The separator comprises a fiber disk fitted over a pair of pins 15 projecting from the bottom of the plunger 9. The separator 14 is provided with a central web 16 which limits the movement of the free ends of the springs toward each other. The separator is also provided with a pair of slots 17 which'permit the springs to expand.

With this construction depression of the finger-piece 10 causes the conical point 8 to enter between and expand the springs thus insuring a positive contact between the contact members and the certain closing of the signal circuit.

As heretofore constructed it has been necessary to disassemble push-buttons in order to observe their construction for purposes of sale or permit their inspection in case the push-button required cleaning or to determine the efficiency of the contact. In order to avoid the disassembling of the pushbutton the body 1 is provided with peepholes 18 arranged in line with. the slot 30 and substantially opposite the circuit closing position of the push-button, (Fig. 1). With this construction a purchaser can readily see and understand the mode of the operation of the push-button. Moreover the peep-hole 18 will permit an inspector to determine if the contact is at fault in the event that the sig nal circuit fails from some unknown cause. Furthermore the peep-hole will permit the insertion of a tool therethrough for the purposes of cleaning the contact members.

Push-buttons of this nature are usually set into an opening in a wall, and in the push-button illustrated, the cap 8 has a larger diameter than the body 1 and is provided with a fiat under face 40 which rests against the face of the wall in which the body 1 is inserted, said face 10 constituting a positioning shoulder to retain the casing in position when the push-button is operated. When the plunger is depressed to close the contacts the pressure against the plunger is transmitted through the spring 11- to the bottom of the tubular body 1 and from the latter to the positioning shoulder 40. It is, therefore, desirable that the body 1 and cap 3 should be firmly connected together, and in order to accomplish this without the necessity of using screws or other parts that are liable to become loosened, I propose to employ the construction shown wherein the end of the body 1 is bent inwardly to form the annular inwardly-directed flange 2 against which the inner portion of the flat face 40 of the cap rests, and the cap 3 is made with the annular depending neck 4: which extends through the opening in the flange 2 and slightly into the body 1. The end of said neck is then spun or swaged under the flange 2 throughout the extent of said flange so as to make an annular flange which underlies the annular flange 2. The neck 4 will preferably be of relatively ductile material which can be easily swaged or spun around the flange 2. By means of this construction a permanent con nection between the casing 1 and the cap 3 is provided which will resist any pressure to which the plunger 10 is submitted and which obviates the use of screws or other fastening means.

As well known to those skilled in the art it is difficult to tighten a. terminal screw upon a terminal wire especially if the terminal wire is composed of a plurality of strands. This is due to the flat construction of the wire engaging shoulder of the screw which as it turns tends to expel the wire from beneath the shoulder. I have discovered that if the wire engaging shoulder of the terminal screw is concaved the turning of the screw will tend to draw the wire inwardly toward the shank of the screw thus insuring the clamping of the wire beneath the shoulder of the screw. Fig. 5 shows a terminal screw 19 having the wire engaging shoulder 20 thereof provided with a concave channel 21. The screw 19 is threaded into a metallic bushing 13 thus obviating the dan-- ger of splitting the fiber bottom 5 which is liable to happen when the screw is carried solely thereby.

It will be evident from an inspection of Fig. 2 that when the screw 19 is turned in to clamp the wire between the shoulder 20 and the corresponding shoulder on the bushing 13, the sharp edge at the periphery of the shoulder 20 will bite into the wire and not only securely clamp the wire, but will insure the formation of a good electrical contact with it.

It will be clear to those skilled in pushbuttons and with the general objects of the present invention in view that changes may be made in the details of the structure, the described and illustrated embodiment thereof being intended as an exploitation of its underlying essentials the features whereof are definitely stated in their true scope in the claims hereto appended.

What is claimed asnew, is:

1. A push button, comprising contact springs normally under tension tending to move their free ends toward each other, a plunger movable toward and away from said springs, a contact member carried by said plunger and constructed to engage and spread apart the free ends of said springs, and a separator also carried by the plunger and acting normally to hold the free end of said springs apart, said separator having slots through which said springs, respectively extend.

2. 1i push button, comprising contact springs normally under tension tending to move their free ends toward each other, a plunger movable toward and away from said springs, a contact member carried by said plunger and constructed to engage and spread apart the free ends of said springs, and a separator also carried by the plunger and acting normally tohold the free ends of said springs apart, said separator comprising a piece of insulating material secured to the plunger and having slots fihrgugh which said springs, respectively, ex-

3. A push button, comprising contact springs normally under tension tending to move their free ends toward each other, a plunger movable toward and from said springs and having a recess formed therein, a contact member positioned in said recess and constructed to engage and spread apart the free ends of said springs, and a separator acting normally to hold the free ends of said springs apart, said separator comprising a disk ofinsulating material secured to said plunger and having slots through which said springs, respectively, extend.

4;. A push button, comprising contact springs normally under tension tending to move their free ends together, a movable contact member mounted to enter between and engage said contact springs, said contact member being tapered inwardly to spread apart said springs when said member is pushed in, and a movable separator normally acting to hold the free ends of said springs apart.

5. push button comprising contact springs normally under tension tending to move their free ends toward each other, a plunger movable toward and away from said springs and having a recess formed therein, a contact member positioned in said recess and constructed to engage and spread apart the free ends of said springs, and a separator acting normally to hold the free ends of said springs apart, said separator being secured to the plunger and extending across the recess therein and also between the s rings.

6. in a push button, the combination with a casing, of contact elements therein and a plunger for operating said elements, said casing comprising a cylindrical tubular body portion having at one end an annular inwardly-directed flange and a head provided with a central opening for the plunger and a flat face to rest on said flange, said head having an annular neck surrounding said central opening, the walls of which are of thin, ductile material, and the end of which is swaged under said flange of the body throug out the extent of the latter, the diameter of the head being greater than that of the body whereby the portion of the flat face that projects beyond the body constitutes a positioning shoulder to engage the face of the wall in which the push-button is supported.

STANLEY ANTHONY. 

